Protective effect of pine ( Pinus morrisonicola Hay.) needle on LDL oxidation and its anti-inflammatory action by modulation of iNOS and COX-2 expression in LPS-stimulated RAW 264.7 macrophages

• Published in: Food and chemical toxicology Vol. 46; no. 1; pp. 175 - 185
• Main Authors: Yen, Gow-Chin, Duh, Pin-Der, Huang, Din-Wen, Hsu, Chin-Lin, Fu, Timothy Yu-Chi
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 2008; New York, NY Elsevier Science
• Subjects: animal models; Animals; anti-inflammatory activity; Anti-Inflammatory Agents, Non-Steroidal; antioxidant activity; Antioxidants - chemistry; Biological and medical sciences; Biphenyl Compounds; Blotting, Western; Cell Line; cell lines; chemical composition; chemical constituents of plants; Chromans - chemistry; Chromatography, High Pressure Liquid; conifer needles; COX-2; Cyclooxygenase 2 - biosynthesis; Cyclooxygenase 2 Inhibitors; dose response; Electrophoretic Mobility Shift Assay; Enzyme Inhibitors - pharmacology; Epicatechin; Flavonoids - chemistry; Free Radical Scavengers - pharmacology; gene expression; human health; Humans; In Vitro Techniques; inducible nitric oxide synthase; Inflammation; iNOS; LDL oxidation; leukemia; lipid peroxidation; Lipopolysaccharides - antagonists & inhibitors; Lipoproteins, LDL - metabolism; low density lipoprotein; macrophages; Macrophages - drug effects; Medical sciences; messenger RNA; Mice; nitric oxide; nitric oxide synthase; Nitric Oxide Synthase Type II - antagonists & inhibitors; Nitric Oxide Synthase Type II - biosynthesis; Oxidation-Reduction; p-Coumaric acid; Phenols - chemistry; Picrates - chemistry; Pine needle; Pinus; Pinus - chemistry; Pinus parviflora; plant extracts; Polyphenols; prostaglandin synthase; protective effect; protein synthesis; Reactive Oxygen Species - chemistry; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger - biosynthesis; solvents; Tetrazolium Salts; Thiazoles; Toxicology; PBS; PGE2; SDS; COX-2; DPPH; DMSO; LDL oxidation; p-Coumaric acid; Inflammation; MTT; ORO; PVDF; LPS; Pine needle; Epicatechin; EAE-PN; DCFH-DA; NOS; TEAC; LDL; RT-PCR; ROS; iNOS; ABTS; Hay; Cyclooxygenase 2; Protective factor; Pinus; Flavonoid; Lipoprotein LDL; Polyphenol; Modulation; Gymnospermae; Softwood forest tree; Lipopolysaccharide; Oxidation; Enzyme; Antiinflammatory agent; Nitric-oxide synthase; Needle; Phenols; Coniferales; Spermatophyta; Oxidoreductases; Macrophage
• ISSN: 0278-6915; 1873-6351
• DOI: 10.1016/j.fct.2007.07.012

The protective effects of pine ( Pinus morrisonicola Hay.) needle on low-density lipoprotein (LDL) oxidation and nitric oxide production in macrophages as well as its bioactive compounds were investigated. Of the four solvent extracts, the ethyl acetate extract of pine needle (EAE-PN) exhibited the strongest scavenging action on free radicals. EAE-PN significantly inhibited copper-induced LDL oxidation through prolonging the lag phase of conjugated dienes formation and decreasing the relative electrophoretic mobility of LDL. Lipid accumulation and foam cell formation were significantly reduced when EAE-PN (75 μg/mL) was added to the medium co-incubated with macrophages cells and copper-induced LDL. EAE-PN also markedly inhibited reactive oxygen species production in RAW 264.7 cells stimulated with lipopolysaccharide (LPS). As regards NO production in cells, EAE-PN showed dose-dependent inhibitory effect on nitric oxide (NO) production in LPS-stimulated RAW 264.7 cells. The inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) protein expressions in LPS-stimulated RAW 264.7 cells were inhibited by EAE-PN. RT-PCR analysis indicated that the iNOS and COX-2 mRNA expression were suppressed by EAE-PN. The major phenolic compounds in EAE-PN were epicatechin and p-coumaric acid by HPLC analysis. The presence of epicatechin and p-coumaric acid in EAE-PN may be partially responsible for the biological action of EAE-PN. Taken together, these results suggest that EAE-PN may provide potential protective effects against LDL oxidation and attenuating excessive NO generation at inflammatory sites; consequently, this may contribute to anti-atherosclerotic and anti-inflammatory effects of EAE-PN.